Exhaust termination ideas?

[Sasquach]

We just returned from our last camping trip and now the CJ comes apart for it's 4.0 head/MPI upgrade. Currently the exhaust is the stock variety and ends just ahead and below the rear bumper and with the top down or the rear window rolled up the exhaust smell and eye irritation is unbearable, as I will be building a new system I was wondering if I would be better off going out the side or straight down as soon as I get past the muffler? I was also currious if anyone ever ran the cat and no muffler? Being in Ca. the cat is requirred but what about the muffler? Maybe it would be too loud anyway but any thoughts?
I know the exhaust will be much cleaner with the MPI but still going to be carbon monoxide coming in the cockpit even if not the current unburned fuel that I get.

 

[CJKrawler]

For the exhaust termination, I would make so that it exits past the body line if you are going to run it out of the back. On the TJ stock, it turns down at the body line, and ends up being about 2 inches past. This will help reduce the amount of CO2 getting into the cab. For the muffler, it would be pretty loud without it, and may not sound all that good. I personally wouldn't run it on the street without a muffler.

 

[Sasquach]

For the exhaust termination, I would make so that it exits past the body line if you are going to run it out of the back. On the TJ stock, it turns down at the body line, and ends up being about 2 inches past. This will help reduce the amount of CO2 getting into the cab. For the muffler, it would be pretty loud without it, and may not sound all that good. I personally wouldn't run it on the street without a muffler.

I think your right on the loud part, just wishin I could reduce the pieces under there.
Now that you remind me when I put the current exhaust on I did cut a couple inches off the tail pipe so it would not stick out past the body/bumper and look a bit cleaner, part off my problem I guess.

 

[dalefan88]

i got a turn down right on my muffler. it dont gas you out like it did when i had a full tail pipe on it.

 

[BrockGrimes]

I run a cat no muffler and mine dumps right under the driver toward the ground.
Sounds good and no fumes.

 

[Sasquach]

I'm guess'n you guys have similar systems but one has a muffler/no cat and one has cat/no muffler and they both turn towards the ground ahead of the axle.
My hope is that the cat has some muffler qualities and would allow me to do the same as you BrockGrimes.

 

[BajaEdition]

Sas, you are going need that muffler for Smog, so make sure you have a bolt on system. when smog is required bolt the muffler in, when not bolt the tial pipe where the muffler goes
I have done such with cats on CA vehicles I street rodded, would make a pipe that bolts in where the cat should be for the biannual smog test.

 

[Sasquach]

Sas, you are going need that muffler for Smog, so make sure you have a bolt on system. when smog is required bolt the muffler in, when not bolt the tial pipe where the muffler goes
I have done such with cats on CA vehicles I street rodded, would make a pipe that bolts in where the cat should be for the biannual smog test.

Thats sorta how my cat is now, I removed and straight piped that section knowing the whole system was getting reworked before smog again or if needed reinstall the cat at any time.

 

[BrockGrimes]

It's does act as a muffler, but if a visual is required then you'll need to stick a muffler on temp.
I saw one that had a short pipe after the cat that clamped on, then was removed and a muffler stuck on for smog.